摘要
目的 :观察 p73基因在γ射线诱发的小鼠淋巴细胞白血病小鼠胸腺和骨髓组织细胞中的表达变化 ,探讨 p 73在辐射致癌中的作用。 方法 :用γ射线照射 BAL B/ c小鼠诱发白血病 ,建立辐射致癌动物模型 ;分别应用 Western印迹和原位杂交(ISH)技术 ,从蛋白水平和 m RNA水平检测小鼠胸腺和骨髓组织中 p73基因的表达情况 ;运用免疫沉淀技术 (IP)检测 P73蛋白的磷酸化水平 ;RT- PCR/ DNA测序技术检测基因突变和变异体的表达。结果 :辐射后癌变组胸腺 /骨髓中的 P73蛋白表达水平明显高于对照组 (P<0 .0 5 ) ;而对照组和辐射未癌变组之间蛋白水平无明显差异 (P>0 .0 5 )。原位杂交 (ISH)结果显示癌变组织中 p73阳性反应和阳性率均明显高于对照组。在癌变组织中发现 P73磷酸化水平明显升高 (P<0 .0 5 )。 RT- PCR发现在癌变组中有 p73变异体γ、δ过表达以及 N末端缺失的突变体 (DTA- p73)表达。结论 :p73可能参与γ射线诱发的小鼠淋巴细胞白血病的发生和发展过程 。
Objective:To investigate the role of p 73 in the process of γ ray induced carcinogenesis by examining the expression of p 73 in mice leukemia model.Methods:According to the histological and pathological results,mice were divided into 3 groups:cancerization group,uncancerization group and control group.Expression of P73 protein and mRNA in thymus and bone marrow was detected with Western blot and in situ hybridization (ISH) respectively.Immunoprecipitation (IP) was done to detect the phosphorylation level of P73 protein.The expression of variants and mutational status was investigated with RT PCR and direct DNA sequencing.Results:In cancerization group,the protein expression and the phosphorylation level in thymus/bone marrow were significantly higher than those of uncancerization group and control group ( P <0.05).Gene variants were detected in the tumor samples and radiation group; there was a large fraction (about 400 bp in size) deletion found in 2 tumor samples.The mRNA level was markedly higher in cancerization group compared with those of the other groups.Conclusion:These results suggest that p 73 may have a potential pathogenetic role in the development and progression of mice leukemia induced by γ ray irradiation.The malignant transformation may be related to overexpression of p 73,especially the overexpression of variants induced by irradiation.The hyperphosphorylation may also contribute to the alteration of P73 activity and thus promote the malignant transformation of cells.
出处
《第二军医大学学报》
CAS
CSCD
北大核心
2003年第7期719-723,共5页
Academic Journal of Second Military Medical University
基金
This work is supported by the National NaturalScience F oundation of China( No.3 0 170 2 82 )
